| SM ISO690:2012|
PAIUK, Oleksandr; STRONSKI, Alexander; VLCEK, Miroslav; KRYSKOV, Tezarii; GUBANOVA, Antonina; OLEKSENKO, Pavel F.. MSP 20 P Raman spectra of As-S glass doped with ytterbium. In: Materials Science and Condensed Matter Physics. Editia a 6-a, 11-14 septembrie 2012, Chișinău. Chișinău, Republica Moldova: Institutul de Fizică Aplicată, 2012, p. 96. ISBN 978-9975-66-290-1.
|Materials Science and Condensed Matter Physics
Editia a 6-a, 2012
Conferința "Materials Science and Condensed Matter Physics" |
Chișinău, Moldova, 11-14 septembrie 2012
Nanostructured chalcogenide glasses have been of great interest due to their remarkable structural, electronic and optical properties demonstrating a wide range of potential applications. Optical transparency in IR spectral region, chemical stability, various photoinduced phenomena such as photodarkening and photobleaching, high refractive indexes and high optical nonlinearities make attractive these materials as photonic devices for ultrafast all-optical switching and data processing. These properties can be controlled by doping them with rare-earth elements or amphoteric metals. This report is concerned with the effect of ytterbium dopant addition to arsenic sulfide glass on its structure by means of Raman spectroscopy. The glasses of composition As2S3, As2S3:Yb 0,5% wt., As2S3:Yb 1% wt. and As2S3:Yb 2% wt. were prepared by melt-quenching technique. Raman spectra were recordered using Fourier spectrophotometer Bruker IFS-55 Equinox with FRA-106 attachment. Nd-YAG laser (excitation wavelength - 1.064 μm). Introduction of Yb leads to the intensity increase of the main band at 346 cm-1 which corresponds to antisymmetric As-(S)-As stretching vibrations in As(S)3/2-pyramids and 192, 227, 236, 365 cm-1 bands, which correspond to the presence of As4S4 nanophase. Intensity of 496 cm-1 band, characteristic for the vibrations of S-S bonds is decreased with the Yb introduction (for As2S3:Yb 2% wt sharply increased). The difference spectra reveal the changes occurred in glass structure upon the variation of composition. From these spectra one can see that addition of Yb resulted in 150 cm-1 and 317 cm-1 bands intensity increase. These bands correspond to vibrations of phasedecomposed S8 rings and to pyramidal structural AsS3 units with additional sulfur atoms involved into (-S-S-) chains and join pyramidal fragments. Our results give evidence that doping of As2S3 glasses with small amount of Yb ions, up to 1 % wt., only slightly affect the short-range order structure of the host matrix. But for Yb concentration more than 1 % wt. the sharp increase o of the additional bands characteristic for the vibrations of non-stoichiometric molecular fragments containing homopolar S-S and As-As bonds was observed. Such changes correlate with data on the thermal properties of these glasses, Tg values sharply decreased if Yb content in glass was more than 1 % wt. The main observed effect under the introduction of ytterbium into As2S3 is the change of relative concentration of the main and nonstoichiometric structural units characteristic for As2S3 glasses. This work was supported partially by the Czech Science Foundation through the grant P204/11/0832  A. P. Paiuk, A. V. Stronski, M. Vlček, et al. Proceedings of SPIE. Vol. 8306, (2011), P. 830617-1 – 830617-4.